Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Status of Application
In response to the Office action mailed on October 24th, 2025, Applicant has amended claims 1, 2, 4, and 6-7. Claims 1-2 and 4-10 are currently pending. Claim 3 has been cancelled.
Specification
The title of the invention is not descriptive. A new title is required that is clearly indicative of the invention to which the claims are directed.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. § 103 which forms the basis for all obviousness rejections set forth in this office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 1, 2, and 4-10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Malinovich et al., US Patent Pub No. 6168965B1, hereinafter “Malinovich” in view of Na et al., US Patent Pub. No. 20180190702A1, hereinafter “Na.”
Regarding claim 1, Malinovich teaches a manufacturing method of a light sensor structure (method for fabricating back illuminated image sensors in column 4, lines 30-32), comprising steps of:
disposing a light-sensing device (image sensing circuits #100 at the light sensitive pixel region disposed in FIG. 4A initially), on a first surface of a substrate (substrate #410);
performing backside grinding (grinding operations on surface in column 2, line 62. Planar erosion surfaces #433 in FIG. 4B and chemical etchant #435 done on the backside to thin the wafer) on a second surface (second surface #320 in FIG. 4B which is on the backside) of said substrate opposing to said first surface (second surface #320 is opposite and above the first surface of substrate #410);
coating a reflection layer (glass, or transparent substrate, #440 in FIG. 4E is a reflection layer and is coated with a compliant layer #450 in FIG. 4F) on said second surface (on second surface #320) by backside metallization (metal contact pads #330 implements backside metallization of second surface #320), and covering said reflection layer (glass, or transparent substrate, #440 on reflection layer in FIGS. 4E-4H) on a region on said second surface opposing to a light-sensing area of said light-sensing device (glass, or transparent substrate, #440 is on the second surface #320 with the transparent substrate #440 arranged opposing the light-sensitive pixel matrix and control circuitry and the image sensor circuits #100).
Malinovich does not teach wherein a coating material for said reflection layer has reflectivity higher than 70% for the light with wavelengths within a first wavelength range between 850 and 1000 nanometers and within a second wavelength range between 1150 and 1450 nanometers.
However, Na teaches wherein a coating material for said reflection layer has reflectivity higher than 70% for the light (Na, metal mirror #1606 has a reflectivity “greater than” 70% in para [0300]) with wavelengths within a first wavelength range between 850 and 1000 nanometers and within a second wavelength range between 1150 and 1450 nanometers (Na, ToF sensor where the wavelength is 850 nm, 940nm, 1050nm or 1.3 to 1.6 micrometers in para [0079] which include the ranges of 850 and 1000 nanometers and 1150 and 1450 nanometers).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the method of manufacturing disposing a light sensing device on a first surface of a substrate and performing backside grind as taught in Malinovich with the use of a coating material for a reflection layer having a reflectivity greater than 70% for light and having a first wavelength range between 850 and 1000 nanometers and a second wavelength range between 1150 and 1450 nanometers as taught by Na. A person of ordinary skill would know to combine Na’s high-reflectivity coating material with these two differing wavelength ranged applied to the backside of the substrate in Malinovich’s device structure would improve the reflection of incident light toward the light sensing device, thereby increasing sensitivity and overall device performance. Thus, Na cures the deficiencies of Malinovich.
Regarding claim 2, Malinovich teaches a manufacturing method of a light sensor structure of claim 1, wherein the coating material for said reflection layer has reflectivity higher than 70% for the light (Na, metal mirror #1606 has a reflectivity “greater than” 70% in para [0300]) with wavelengths between 850 and 1450 nanometers (Na, absorption layer #106 which is also a form of coating material has wavelength between 850 nm to 940 nm for a GiSi in para [0143]).
Regarding claim 4, Malinovich in view of Na teaches the manufacturing method of a light sensor structure of claim 3, wherein the coating material for said reflection layer has reflectivity lower than 70% for the light (Na, reflectivity lower than 70% such as 50% and 60% in para [0300] which include reflectivity lower than 70%) with wavelengths between 1050 and 1100 nanometers (Na, ToF sensor with a GeSi absorption material where the wavelength is 850 nm, 940nm, 1050nm or 1.3 to 1.6 micrometers in para [0079] which includes the range of 1150 and 1100 nanometers).
Regarding claim 5, Malinovich in view of Na teaches the manufacturing method of a light sensor structure of claim 1, wherein a coating material for said reflection layer has reflectivity higher than 70% for the light (Na, metal mirror #1606 has a reflectivity “greater than” 70% in para [0300] and reflectivity greater than 70% with reflectivity values like 80-95% listed in para [0300]) with wavelengths within a first wavelength range between 850 and 1000 nanometers (Na, ToF sensor where the wavelength is 850 nm, 940nm, 1050nm or 1.3 to 1.6 micrometers in para [0079] which include the ranges of 850 and 1000 nanometers), and has reflectivity lower than 70% for the light (Na, reflectivity lower than 70% such as 50% and 60% in para [0300] which include reflectivity lower than 70%) with wavelengths between 1050 and 1100 nanometers (Na, ToF sensor where the wavelength is 850 nm, 940nm, 1050nm or 1.3 to 1.6 micrometers in para [0079] which include the ranges of 1050 and 1100 nanometers).
Regarding claim 6, Malinovich teaches a manufacturing method of a light sensor structure (method for fabricating back illuminated image sensors in column 4, lines 30-32), comprising steps of:
disposing a light-sensing device on a first surface of a substrate (image sensing circuits #100 at the light sensitive pixel region disposed in FIG. 4A initially);
performing backside grinding (grinding operations on surface in column 2, line 62. Planar erosion surfaces #433 in FIG. 4B and chemical etchant #435 done on the backside to thin the wafer) on a second surface (second surface #320 in FIG. 4B which is on the backside) of said substrate opposing to said first surface second surface #320 is opposite and above the first surface of substrate #410;
coating a reflection layer on a backplate (glass, or transparent substrate, #440 in FIG. 4E is a reflection layer and is coated with a compliant layer #450 in FIG. 4F on a protective substrate #410 in FIG. 4F which is backplate); and
bonding said backplate to a second surface (protective substrate #410 is bonded to the second surface #320) of said substrate opposing to said first surface (second surface #320 is opposed to first surface #310 as shown in FIG. 4E), and covering said reflection layer (glass, or transparent substrate, #440 on reflection layer in FIGS. 4E-4H) on a region on said second surface opposing to a light-sensing area of said light-sensing device (glass, or transparent substrate, #440 is on the second surface #320 with the transparent substrate #440 arranged opposing the light-sensitive pixel matrix and control circuitry and the image sensor circuits #100).
However, Na teaches wherein a coating material for said reflection layer has reflectivity higher than 70% for the light (Na, metal mirror #1606 has a reflectivity “greater than” 70% in para [0300]) with wavelengths within a first wavelength range between 850 and 1000 nanometers and within a second wavelength range between 1150 and 1450 nanometers (Na, ToF sensor where the wavelength is 850 nm, 940nm, 1050nm or 1.3 to 1.6 micrometers in para [0079] which include the ranges of 850 and 1000 nanometers and 1150 and 1450 nanometers).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the method of manufacturing disposing a light sensing device on a first surface of a substrate and performing backside grind as taught in Malinovich with the use of a coating material for a reflection layer having a reflectivity greater than 70% for light and having a first wavelength range between 850 and 1000 nanometers and a second wavelength range between 1150 and 1450 nanometers. A person of ordinary skill would know to combine Na’s high-reflectivity coating material with these two differing wavelength ranged applied to the backside of the substrate in Malinovich’s device structure would improve the reflection of incident light toward the light sensing device, thereby increasing sensitivity and overall device performance. Thus, Na cures the deficiencies of Malinovich.
Regarding claim 7, Malinovich in view of Na teaches the manufacturing method of a light sensor structure of claim 6, wherein the coating material for said reflection layer has reflectivity higher than 70% for the light (Na, metal mirror #1606 has a reflectivity “greater than” 70% in para [0300]) with wavelengths between 850 and 1450 nanometers (Na, absorption layer #106 which is also a form of coating material has wavelength between 850 nm to 940 nm for a GiSi in para [0143]).
Regarding claim 9, Malinovich in view of Na teaches manufacturing method of a light sensor structure of claim 8, wherein the coating material for said reflection layer has reflectivity lower than 70% for the light (Na, reflectivity lower than 70% such as 50% and 60% in para [0300] which include reflectivity lower than 70%) with wavelengths between 1050 and 1100 nanometers (Na, ToF sensor with a GeSi absorption material where the wavelength is 850 nm, 940nm, 1050nm or 1.3 to 1.6 micrometers in para [0079] which includes the range of 1150 and 1100 nanometers).
Regarding claim 10, Malinovich in view of Na teaches the manufacturing method of a light sensor structure of claim 6, wherein a coating material for said reflection layer has reflectivity higher than 70% for the light (Na, metal mirror #1606 has a reflectivity “greater than” 70% in para [0300] and reflectivity greater than 70% with reflectivity values like 80-95% listed in para [0300]) with wavelengths within a first wavelength range between 850 and 1000 nanometers (Na, ToF sensor where the wavelength is 850 nm, 940nm, 1050nm or 1.3 to 1.6 micrometers in para [0079] which include the ranges of 850 and 1000 nanometers), and has reflectivity lower than 70% for the light (Na, reflectivity lower than 70% such as 50% and 60% in para [0300] which include reflectivity lower than 70%) with wavelengths between 1050 and 1100 nanometers (Na, ToF sensor where the wavelength is 850 nm, 940nm, 1050nm or 1.3 to 1.6 micrometers in para [0079] which include the ranges of 1050 and 1100 nanometers).
Response to Arguments
Applicant’s arguments have been considered but they are not persuasive.
Applicant argues in substance:
“The very language used by Malinovich-"transparent substrate" and "glass"-indicates that element 440 is designed to transmit light, not reflect it. A transparent glass substrate, by its very nature as a "transparent" element, is designed for high optical transmission and consequently has inherently low reflectivity. This is a fundamental principle of optics: materials selected for transparency are specifically chosen for their ability to transmit light with minimal reflection.”
The argument is not persuasive. As noted in the claim mapping above, Malinovich does teach a reflection layer and under the broadest reasonable interpretation a glass or transparent substrate #440 as shown in Malinovich is a reflection layer. Glass reflects a portion of incident light at its surface, even while transmitting light. Thus, the cited transparent substrate reasonably meets the claimed reflection layer as it is capable of reflecting light. Moreover, a transparent substrate or glass both transmits and reflects light because of the mismatches of the refractive index at interfaces. In the current form, the claimed “reflection layer” does not require 100% reflectivity and a mirror type of coating. Therefore, a reflection layer under the broadest reasonable interpretation is any layer capable of reflecting light and does not require complete reflection. Thus, the reflection layer is taught by Malinovich. It would be apparent to a person of ordinary skill in the art that the prior art teaches a reflection layer.
As amended, both Claims 1 and 6 now explicitly recite that the coating material for the reflection layer has:
"reflectivity higher than 70%for the light with wavelengths ·within a first wavelength range between 850 and 1000 nanometers and ,vi thin a second wavelength range betiveen 1150 and 1450 nanometers”
This dual-wavelength-range limitation requires high reflectivity (> 70%) in both the first infrared range (850-1000 nm, commonly used for proximity sensors operating at 940 nm) and the second infrared range (1150-1450 nm, used for certain ToF applications at ~1300 nm).
Malinovich's transparent glass substrate 440, being designed and selected specifically for its transparency (i.e., high transmittance and low reflectivity), does not and cannot satisfy this limitation. The very descriptor "transparent" is fundamentally inconsistent with ">70% reflectivity." No reasonable interpretation of Malinovich's disclosure supports a finding that element 440 exhibits >70% reflectivity in either wavelength range, let alone both.
The applicant’s argument is not persuasive because it is improperly uses the primary reference of Malinovich individually. The rejection is based on a combination of references of Malinovich and Na. The secondary reference of Na teaches the limitation of a reflection layer having a reflectivity greater than 70% within the recited wavelength ranges in the 850 nm – 1000 nm and 1150 nm – 1450 nm range is taught by Na and not Malinovich. A person of ordinary skill would know to combine Na’s high-reflectivity coating material with these two differing wavelength ranged applied to the backside of the substrate in Malinovich’s device structure would improve the reflection of incident light toward the light sensing device, thereby increasing sensitivity and overall image sensing device performance. Na teaches a coating material for said reflection layer has reflectivity higher than 70% for the light by showing a metal mirror #1606 has a reflectivity “greater than” 70% in para [0300] with wavelengths within a first wavelength range between 850 and 1000 nanometers and within a second wavelength range between 1150 and 1450 nanometers by having a ToF sensor where the wavelength is 850 nm, 940nm, 1050nm or 1.3 to 1.6 micrometers in para [0079] which includes the ranges of 850 and 1000 nanometers and 1150 and 1450 nanometers. Thus, Na teaches the amended claim limitation.
Additionally, Applicant notes that the Examiner's mapping of the claim limitations to Malinovich contains a structural error. The Examiner identifies "metal contact pads #330" as implementing backside metallization of second surface #320. However, as shown in Malinovich's FIG. 4E, pads #330 are disposed on the front side of the device (the surface facing protective substrate 410), not on the second surface (backside #320). Therefore, even setting aside the fundamental transparency-versus-reflectivity issue discussed above, Malinovich does not teach the claimed step of "coating a reflection layer on said second surface by backside metallization.
The applicant’s argument is not persuasive because Malinovich taken as a whole explicitly teaches a “backside metallization” as a process step. Malinovich cites “a metal film is formed over exposed backside surface 320” in column 7, lines 42-43. In addition, even if pads #330 of Malinovich are disposed on the front side of the image sensor device, this does not limit metallization exclusively to the front side, nor does it teach away from forming metallization on the backside of the substrate. In the image sensor, backside metallization is done to reduce frontside obstruction of incoming light improves light collection and sensor sensitivity and helps with routing electrical signals. Thus, a person of ordinary skill would know that the art of Malinovich teaches backside metallization into the image sensor and is an obvious process step.
Examiner would suggest in the interest of compact prosecution that the Applicant align the claim limitations in a manner to overcome the prior art. The new claim limitations that were amended in claim 1 still teach Malinovich and Na in combination. In addition, the Applicant is encouraged to amend the claims to clearly define the reflection layer in a manner that differs from the prior art. Examiner is available for an interview to discuss any rejections or claim amendments.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MEHEK AHMED whose telephone number is (571)272-4155. The examiner can normally be reached Mon-Thurs 9:00AM-7:00PM.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Marlon Fletcher can be reached at 571-272-2063. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/MEHEK AHMED/Examiner, Art Unit 2817
/MARLON T FLETCHER/ Supervisory Primary Examiner, Art Unit 2817
Prosecution Insights